1. Field of the Invention
The present invention relates to a power transmitting apparatus, and more particularly, to an apparatus and a system for transmitting and receiving power wirelessly.
2. Description of the Related Art
Recently, wireless power transmission technology that can wirelessly provide power to a variety of mobile devices or industrial robots has become an issue. Inductive coupling and radiative coupling are typically used for wireless power transmission.
In inductive coupling, a number of coils are used such that a magnetic field is strongly induced in one direction, and when coils which resonate at a similar frequency become very close to each other, coupling takes place, and power transfer thereby occurs between the coils. However, the inductive coupling enables power transfer within a very limited range, and power transfer is not possible if the coils are not accurately aligned with each other.
In contrast, in radiative coupling, antennas such as a monopole or a planar inverted F antenna (PIFA) are used to radiate power while time varying electric fields and magnetic fields interact with each other. If two antennas have the same frequency, power can be transferred between the antennas according to the polarization properties of an incident wave. However, in this case, power is radiated in all directions, and thus efficient power transmission is hard to be achieved.